Organic Ag vs Global Climate Change

by Catherine Haug

Is there a connection between global warming and industrial agriculture? If modern society reverted to traditional, organic methods of food production, could we mitigate or perhaps reverse climate change?

The Organic Consumer’s Association (OCA) believes that the answers are YES and YES. They cite the following projections. If we reverted to organic food production:

By converting the world’s 3.5 billion acres of farmland to organic, we would sequester 40% of global greenhouse gas emissions, removing excess CO2 from the atmosphere and storing it in the soil, where it belongs.

By also managing the world’s 11 billion acres of pastures, rangelands and forests with organic methods we could potentially sequester 100% of greenhouse gas emissions.

Industrial Ag: What makes your corn field grow?

Today many people have come to accept that the only way to grow crops is by applying chemical fertilizers, and protecting them from disease with the use of chemical pesticides and herbicides. Others, recognizing the problems created by over-reliance on these chemicals, have come to accept GMO seeds as a viable option.

And, indeed, for a system where livestock are kept in confinement, the use of chemicals and GMO crops to provide the feed for these hapless animals is a given.

But, the use of these chemicals comes with a cost: over-production of greenhouse gasses. How is this so?

Fixing Nitrogen

First we must understand what it takes for a plant such as corn to grow. It needs four elements: carbon, oxygen, hydrogen and nitrogen. The first three come from decayed organic matter, our air, and water.

But nitrogen is more difficult. While it is present in our air as nitrogen gas (N2), this is a very inert form, meaning that it is quite happy to stay as it is and requires a huge amount of bribery (energy) to convert it to other forms. Most plants cannot utilize it in this form; it must be “fixed,” or converted to a less stable form, to be useable.

This method has served humanity well, ever since the time when crops were first domesticated and man settled down to grow them.

But then came the 20th century and WWII. The military machine developed a way to convert nitrogen and hydrogen gas from the air into explosive ammonium nitrate, using the energy produced by the burning of cheap petroleum and other fossil fuels. When the war was over, this military industrial machine turned this same process to increasing their wealth by fixing nitrogen for fertilizers.

But, of course, the side effect of burning fossil fuels is the release of vast amounts of CO2 and toxic gasses into the atmosphere, which we now know causes the “greenhouse effect” of warming the earth’s atmosphere. And make no mistake, the fixing of nitrogen by burning fossil fuels is a major contributor to this problem.

But could the abandonment of industrial fixed nitrogen in favor of organic methods (legumes) really reverse the problem?

I believe the answer is yes, for two main reasons:

Reduction in greenhouse gas emissions;

Sequestration of carbon in the soil, through the roots of the plants.

Organic carbon sequestration

We all learned in grade school that we breathe in O2 and exhale CO2. Plants take-up the CO2 and, with the help of the sun’s energy, convert the gas to sugars and starches, releasing O2 back into the atmosphere. It’s a perfect cycle that has kept the planet going for eons.

The sugars and starches produced by the plants are stored primarily in their roots, as fuel to support their growth over their lifetime. And when the plant dies, the roots decay and the stored fuel is incorporated in the soil as organic matter. In this way, the CO2 from the air is sequestered in the soil for future generations of life.

The deeper the roots, the better. The most efficient ‘crops’ for sequestration are native forests and grasslands, whose deep roots can sequester far more carbon in the soil as organic matter, than today’s industrial farms. Per the OCA article:

“Before carbon-sequestering forests and grasslands were ravaged by chemical-intensive industrial agriculture (and industrial forestry), organic matter generally composed 6-10% of the soil volume, three to six times the 1-3% levels typical of today’s industrial agriculture soils.”

Shallow-rooted crops, such as domesticated corn and wheat, also sequester carbon when their roots are tilled into the soil. But because only the top few inches of soil are enriched by the decayed matter, the sequestering is not as effective as when deep-rooted crops are used.

For this reason, ESP encourages our community to replace typical lawn grass with native grasses. See Native Grasses for the Missoula Area for ideas. Swan River Gardens sells a native grass seed mix. Of course, replacing isn’t just a matter of sowing seed on an existing lawn. You first need to dig up the existing lawn, then till the ground several times. Or use sheet mulching to build up new soil on top of the existing lawn, to smother it.

And we should also be working with local government to restore native grasslands in our area, and to protect essential forests from development.

Conclusion

Today, growing crops on industrial fertilizers results in a significant net gain of CO2 into the atmosphere (CO2 released by fertilizer production less CO2 sequestered in the soil). But if we revert to more traditional organic methods, CO2 balance is restored in this system.

The big questions are:

How do we accomplish this before it’s too late; before we’ve passed the tipping point? How do we stop the industrial ag machine?

How can we stop the ravaging of our forests and grasslands? How can we restore those we’ve already lost?

How do we convince the masses of the true cost of “cheap” industrially-produced foods, so they will vote with their wallets?

This entry was posted on Tuesday, December 29th, 2009 at 12:11 pm and is filed under Agriculture, Energy. You can follow any responses to this entry through the RSS 2.0 feed.
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